Now remember that combustion analysis is just an analytical process that helps us to determine the empirical formula of a compound. Combustion analysis is accomplished through the use of a combustion apparatus. Now this apparatus is where the sample is vaporized and goes through combustion by traveling between chambers.

So here we have a basic type of combustion apparatus. Here it has chambers A through D. What happens first is that we have to place our sample within chamber A and we allow oxygen gas to enter this. Remember a key component of a combustion reaction is the presence of O₂ as a reactant. Now chamber A, we've placed our sample within it and this is where the sample is vaporized so it's changed into a gaseous state.

It then travels into chamber B and chamber B is where hydrogen is converted into water. So if this sample possesses hydrogen, it gets converted into water and the non-metal portions of this sample get converted into some type of gas. Now if that gas, if that nonmetal happens to be carbon, it's normal for it to become CO₂. We talked about non-hydrocarbons, so if it's nitrogen it would become NO₂. If it's sulfur it becomes SO₂. If it's one of the halogens it becomes a diatomic molecule.

Now traveling out of chamber 2. This is where we have the splitting of water and our gas in chamber C. This is where water is being trapped and again based on the identity of the non-metal we could make different types of gases. CO₂ if the non-metal is carbon, NO₂ if it's nitrogen, SO₂ if it's sulfur, and then one of the diatomic halogens if it happens to be a halogen.

Now what comes out after all of this is any excess oxygen that remains, and this is a possibility. Sometimes a combustion reaction can happen in an environment that's rich in oxygen. The reaction takes place, but there's still oxygen all over the place. So just remember, combustion analysis requires the use of a combustion apparatus. And now that we've seen this apparatus, let's take a look at some different types of combustion analysis questions that kind of go hand in hand with understanding this apparatus.